Letter-opener



A. BLIST.

LETTER OPENER.

A?PLlC/\T|0N FILED JAN.|6,1920- Patented Mar. 15

ATTORNEY UNITED STATES PATENT QFFIQE.

ALBERT BLIST, OF SAN FRANCISCO, CALIFORNIA.

LETTER-OPENER.

Application filed. January 16, 1920.

junction to do the cutting. Combined with these blades 1 adapt a gage to limit the depth of cut, and avoid injury to the contents of the envelop.

Other accessories of the instrument will appear hereinafter, and will be fully described in connection with the accompany ing one sheet of drawing, in which i have illustrated the invention and in which;

Figure 1 is a sectional elevation showing the housing of the instrument, the blades therein, the gages, and the other parts.

Fig. 2 is a top view of the instrument.

Fig. 3 is a cross-section through the middle of the instrument, showing the interior of the frame or housing, and the mechanism by which the envelops are guided, gaged and out.

Fig. 4 is an end elevation of the instrument.-

In the figures The frame or housing 1 supports the operative mechanism of the instrument, including a guide plate, 2, against which an envelop is placed, and a spring 3 to bear against the envelop, and hold it against the guide plate.

At each end of the housing is a rotatable shaft box at, held in any position by a set screw 5. A shaft 6 is eccentrically journaled in the box 4t, so as to be adjusted by the rotation of the same.

A knife 9 and curved stop 10 are mounted on shaft 6 by means of arms 8, or otherwise. The knife is preferably of helical form, and co-acts with a cutting bar 11, secured to the housing 1, the edge of the envelop being cut off between them.

The curved stop is of approximately cy- Specification of Letters Patent.

Patented Mar. 15, 1921.

Serial No. 351,881.

lindrical form, and serves as a gage or, stop to limit the depth of the cut made by the knife and cutter bar. For this purpose the envelop rests upon the stop, and rides thereon as it and the helical knife are carried around by the rotation of the shaft. The

bottom of the recess 12 in the housing may constitute an additional stop for the en-' velop.

The crank, or handle 7 is preferably so placed that when it hangs. down, stop 10 is uppermost, and an envelop inserted into the instrument will come to rest upon the shield. A rotation of the shaft will then bring the knife into operation, and the edge of the envelop be cut off.

In operation; an envelop, being placed against guide plate 2, is pushed down until it comes against gage stop 10, or the bottom of recess 12, or both. The knife is then rotated and the edge of the envelop thereby cut off, as already explained. During this operation the envelop is held by spring 3 against the opposing surface of guide 2.

lVhat I claim as new and desire to secure by Letters Patent is A letter opener, comprising, in combination, a housing having a guide projecting upward from its top, a slot adjacent said guide and'a spring approximating said slot and guide, and adapted to hold an envelop against said guide when inserted in said slot, a fixed cutter bar inside the housing and adjacent said slot, a rotary shaft journaled in the housing below the slot, a rotary helical knife mounted on said shaft and adapted to co-act with said fixed cutter bar to out the edge of an envelop inserted in said slot and held therein by said spring, a rotary depth gage also mounted on said shaft, approximating the edge of said fixed cutter bar and adapted to limit the depth to which an envelop may be inserted in said slot, said rotary knife and gage so placed on said shaft as to act consecutively and not simultaneously on an envelop, and means for rotating said shaft.

In testimony that I have invented and claim the foregoing, I have hereto set my hand the 9th day. of January, 1920.

ALBERT BLIST. 

